A group close to Al Qaeda-linked militant Abu Musab al-Zarqawi (search) is offering a $280,000 reward for the killing of Iraqi interim Prime Minister Iyad Allawi (search), according to a statement posted Sunday on an Islamic Web site.

The statement by the group Khalid bin Al Walid Brigade called Allawi an "American stooge" and said that its assassins were ordered to kill the prime minister and other Iraqi leaders.

"We vowed to God to kill you. Your head and those of your cronies are wanted by Sheik Abu Musab al-Zarqawi," the statement said. "If we cannot deliver the reward of 200,000 Jordanian dinars [$280,000] to whoever gets us Allawi's head, his reward will be delivered in Heaven by Almighty God," it said.

U.S. authorities last week have raised to $25 million from $10 million the reward for information leading to the arrest of al-Zarqawi, a Jordanian suspected of masterminding a wave of terror attacks in Iraq. Al Qaeda leader Usama bin Laden (search) has a $50 million bounty on his head.

Al-Zarqawi's Al Qaeda-linked terror group has claimed responsibility for the attacks on police and security forces in Iraq that have killed hundreds. He is also believed to be behind the beheading of two hostages, an American businessman and a South Korean translator.

In its statement, the group said Allawi should step down and leave Iraq.

The group also lashed out at the Iraqi interim president, Ghazi al-Yawer, describing him as a traitor.

"God willing, there will be nonstop long lines of car bombs," said the statement.

In April, an audio recording attributed to bin Laden and posted on an Islamic web site offered rewards in gold for the killing of top U.S. and U.N. officials in Iraq or of citizens of any nation fighting there.

The statement by al Zarqawi's group did not explain why it put the reward in Jordanian dinars, rather than Iraqi dinars or the favorite currency in the region, the U.S. dollar.